Improvement in compositions to be



rrnn STATES PATENT OFFICE.

FREDERICK NIEDERHEITMANN, OF AIX-LA-CHAPELLE, PRUSSIA.

IMPROVEMENT IN COMPOSITIONS TO BE APPLIED T0 WGOD FOR SOUNDING-BOARDS 0FMUSICAL INSTRUMENTS.

Specification forming part of Letters Patent No. 150,074, dated April21, 1874; application filed March 26, 1874.

To all whom ct may concern:

Be it known that I, FREDERICK NIEDER- HEITMANN, of Aix-la-Chapelle, inthe Kingdom of Prussia, have invented a new and Improved Composition tobe Applied to the Sounding-Boards of Pianos, Violins, Violoncellos,820.; and I do hereby declare that the following is a full, clear, andexact description of the same.

The invention relates to a novel composition of matter whereby thoseproperties of wood which adapt it to use for the soundingboards ofpianos, guitars, and other musical instruments may be preserved for anindefinite period, sounding-boards not only retaining their peculiarquality, but undergoing an actual change for the better. The inventionwill first be fully described in. connection with all that is necessaryto a full understanding thereof, and then pointed out in the claim.

My composition consists of turpentine, four parts; boiled linseed-oil,one part; Canada balsam, one part. These ingredients should be of thefinest quality and greatest purity to produce their maximum efiect,although those of an inferior quality, and in somewhat varyingproportions, will embody the principle of my invention, and evolve aneffect different only in degree.

After a thorough intermixture of the in gredients the composition iswarmed and applied (preferably with a brush) on the soundingboard or thewood out of which it is to be prepared, the board or wood being alsoheated to about 7 centigrade (Celsius) After the first coat iscompletely dried, a second one is in like manner applied. After thisdries, the operator will perceive that the pores of the wood have beenpretty well filled, and a shiny face has been to some extent alreadyformed. This is made homogeneous by a third coat.

The invention has been practically exemplified to the satisfaction ofthose engaged in'the manufacture of sounding-boards in this country andin Europe, many of these parties havin g recently adopted and put it inpractice.

The effect of displacing air and other elements, and causing thispreparation to permeate the pores of wood, is to provide it with ahomogeneous sounding medium. The latter is durable, while the deadeningeffect of wood decreases with time, the instrument being thus foundactually to improve with time and age. The pores being filled also by apractically water-a1id-air-proof material, the natural elasticity offiber is unimpaired by the absorption of moisture or any otherdeleterious element, while changes of temperature cease to exercise anyperceptible effect.

The manufacturer has been heretofore compelled to exercise great care inthe selection of his material, and even then to discard from eighty toninety per cent. of his wood, while with my process fully ninety percent. of the same carefully-selected wood can be readily employed.Another advantage of my composition is, that it renders unnecessary theusual coat of varnish, which always, more or less, injures the soundingqualities of the wood.

Having thus described my invention, what I claim as new is- I Acomposition of turpentine, boiled oil, and Canada balsam, prepared andapplied to sounding-boards or the wood from which they are to be made,as and for the purpose specified.

The above specification of my invention signed by me this 19th day ofFebruary, A. D. 1874.,

FREDERICK NIEDERHEITMANN.

Witnesses:

v LOUIS BERTEL, ALFRED NAUS.

